Rainbow dust

[Tricky]

Lately in the development trunk the dust has/or was rainbow coloured. It got me thinking of redshift. Would it be possible or desirable to have the dust redshift. I.e. shift to blue in the fore-screen and shifting to red in the aft-screen. Port and starboard screens can have the dust blue to red/left to right.

[Eric Walch]

Dust is generated with a shader. I am no shader writer, but I think this should be possible to add into the shader. Nice for a custom oxp

Although..... I think the shader is probably not able to determin the view direction.

[JensAyton]

View direction yes, velocity no. It could do something while warping, though (and can of course be overridden by an OXP).